The mechanisms by which alcohol affects the excitability of the nervous system are poorly understood. This project investigated the cellular and molecular mechanisms involved in the regulation of nerve cell excitability and the effects of ethanol on those mechanisms. Excitability mechanisms were studied in adult rat dorsal root ganglion neurons cultured in the absence of serum and exogenously added nerve growth factor (NGF) using the whole-cell patch-clamp technique. Current-clamp recording revealed the presence of action potentials in these neurons that were inhibited by tetrodotoxin (TTX). With voltage- clamp recording, both an initial inward and a later outward current were observed. The inward current was pharmacologically separated into a transient sodium current and a sustained calcium current. The outward current was found to be a slowly activating potassium current that was inhibited by tetraethylammonium (TEA). The inward sodium current had a maximal amplitude near -10 mV and was completely blocked by TTX. In previous studies on DRG neurons in vivo and cultured in the presence of serum and NGF, both TTX-sensitive and TTX-resistant action potentials have been observed. By contrast, in this study only TTX-sensitive action potentials and TTX-sensitive sodium currents were found in neurons cultured in the absence of serum and NGF. The observations suggest that serum and/or NGF may regulate the expression of voltage- gated ion channels. In addition, the effect of ethanol was studied on several voltage-activated ion currents in different types of mammalian neurons; it was found to have little or no effect on these currents in concentrations of 100 mM or less. GRAMT=Z01AA00481 IL-1 is a major pro-inflammatory cytokine that induces HIV transcription in macrophages. The understanding of the regulation of IL-1 production would lead to possibilities to suppress its undesirable effects. Earlier we have purified a novel factor that induces IL-1 production in macrophages. Based on the N terminal sequence several unsuccessful attempts were made to clone this factor from cDNA libraries. The failure of these experiments is probably due to the degeneracy of the nucleotide sequence deduced from the protein sequence. HIV infection induces dementia in many patients. This dementia is related to the presence of HIV infected macrophages in the CNS. What causes the initial transcriptional activation of HIV in the brain, or the migration of infected cells, is now known, but it is possible that this is due to the presence of pro-inflammatory cytokines. Therefore we initiated studies to analyze the expression of pro-inflammatory cytokine genes (IL-1, TNFalpha) in the mouse brain. The results suggest that under basal conditions these genes are transcribed at low levels, detectable only by PCR analysis. However, i.v. exposure of the animal to known inducers of inflammatory cytokine production has markedly increased the levels of IL-1 and TNFalpha mRNAs strong stimulatory effect in all of the brain areas studied. These results suggest that pro-inflammatory cytokine production in the brain might be strongly affected by inflammatory processes elsewhere. Thus it is possible that careful anti-inflammatory treatment of AIDS patients would reduce the speed of dementia development.